Scanning devices of this type are generally called scanners and are known in numerous variants and in practical use. Constant technological progress makes it desirable in the field of the photographic copying devices to scan originals not only in the three classical base colours red, blue and green, but to scan them spectrally in order to generate the prerequisites for a refined exposure control. While spectral photometers suitable in this respect are known and available, the realization of a spectrally operating scanning device for photograph copiers is associated with significant practical difficulties because of the associated high cost.
The present invention is now intended to overcome this difficulty and to disclose a scanning arrangement which provides the basis for a spectral point form measurement of a transparent object and at a manufacturing cost acceptable in practice.